1. Field of the Invention
The present invention relates to a connector shield case.
2. Description of the Related Art
Conventionally, an electric wire, such as a cable, is connected to a circuit board, such as a printed circuit board, by means of a receptacle connector for receiving a plug connector connected to an end portion of the electric wire. The receptacle connector is configured such that a shield case formed of a metal plate is attached around a housing (refer to, for example, Japanese Patent Application Laid-Open (kokai) No. 2004-192838).
FIG. 11 is a perspective view of a conventional receptacle connector. In FIG. 11, reference numeral 301 denotes a receptacle connector to be mounted on a circuit board. The receptacle connector includes a housing 302 for holding terminals 306, and a rectangular, tubular shield case 303 which surrounds the housing 302. The shield case 303 is formed by bending into a rectangular, tubular shape a single metal blank having a predetermined shape, in the form of a development of the shield case 303. Opposite ends of the metal blank are joined together at a joint portion 304. In this case, an elastic lock piece 307 is bent inward at a bend portion 308, and then the metal blank is formed into the rectangular, tubular shape. The elastic lock piece 307 is engaged with a lock recess portion of an unillustrated plug connector, thereby locking the received plug connector.
Mounting projecting-leg portions 305 extend downward from opposite side ends of a bottom portion of the shield case 303. The projecting-leg portions 305 are inserted into corresponding through holes formed in an unillustrated circuit board and are fixed by soldering. By this procedure, the receptacle connector 301 is fixedly mounted on the circuit board.
However, the conventional shield case 303 fails to sufficiently increase the length of the projecting-leg portions 305, potentially resulting in low mounting strength in mounting the receptacle connector 301 onto a circuit board. This is because the shield case 303 is formed by bending a single metal blank having a predetermined shape, in the form of a development of the shield case 303. In a developed state as viewed before bending is performed, the projecting-leg portions 305 project into a bottom portion of the shield case 303 from opposite sides. The metal blank is bent along opposite side lines of the bottom portion, whereby the projecting-leg portions 305 extend perpendicularly to the bottom portion. Thus, the width of the bottom portion limits the feasible maximum length of the projecting-leg portions 305.
Particularly, in the case where an interface standard or the like requires formation of a lock piece on the bottom portion, the feasible maximum length of the projecting-leg portions 305 is further limited, potentially resulting in the projecting-leg portions 305 failing to extend through corresponding through holes formed in a circuit board. In this case, since the projecting-leg portions 305 do not project from the back side of the circuit board, soldering becomes insufficient, resulting in low mounting strength in mounting the receptacle connector 301 onto the circuit board.
In the case of the illustrated receptacle connector 301, since the elastic lock piece 307 is formed by bending inward a metal blank at the bend portion 308, the projecting-leg portions 305 can assume a certain effective length. However, a bottom plate is absent in a wide region of the bottom portion other than a region in the vicinity of the bend portion 308. As a result, the shield case 303 fails to exhibit sufficient shielding effect. Also, difficulty is involved in securing sufficient strength.